Question

Superheated water vapor enters a well-insulated throttling valve at
p1 = 1 atm and t1 = 600�F . At the valve exit, an engineer reports
that the exit state is superheated vapor and the thermometer reads
t2= 800�F. Assume the effects of kinetic and potential energy are
negligible.
a) Determine the entropy production in the valve, in Btu/lb��R. b)
Can the reported information at the valve exit be possible?